Re: Interact stepper ball screw reduction ratios

Hi mine has "big" size 42 "Superior" steppers - It's a 1979
machine. I've completely junked the BP electronics and fitted three
Compumotor S8 series micro-stepping drives, an AhHa controller card
and software that came with the mill. The advantage with these
drives (if you can get them) is that they have an integral power
supply, and output up to 120V and 8 Amp per phase with up to 56,000
steps per rev. Of course the latter is meaningless in reality,
hence trying to come to terms with an optimal resolution, drive
ratio. I've got backlash in the X axis (2 thou) so I'm getting the
ball-screw rebuilt locally (Nottingham in the UK). The Y axis is
just OK (about 0.3 thou) as its only going to get used for hobby
use. I also plan to convert the varispeed spindle set up into a
simple belt drive VFD combination as I have a VFD and the varispeed
bushes need servicing anyway.
Fred
--- In CAD_CAM_EDM_DRO@yahoogroups.com, "Lance Hopper"
<snaggletto@c...> wrote:

> I've got a Series I cnc, BOSS 5 I think. It does have the big
> steppers on it. My manual also states 1:1 ratio, although I

haven't

> gotten into the machine to verify. I do hope mine is at 2:1

also. I

> was concerned with this as I have some ~700 oz/in max servos that

I

> was hoping to install. I figured I would need at least a 2:1

ratio

> if not 4:1. Good luck with your retrofit. Please keep us updated.
>
> --- In CAD_CAM_EDM_DRO@yahoogroups.com, "Raymond Heckert"

<jnr@a...>

> wrote:
> > I've got a SERIES I, and it's a 1:1 ratio. Do you have the big
> SIGMA or
> > SUPERIOR size 42 stepper motors? Where are you located?
> >
> > RayHex
> >
> > ----------
> > > From: bazer_20002000 <cncfred@b...>
> > >
> > > Im rebuilding a Series 1, Boss 3 BP fitted with stepper

motors.

> > > Currently the belt drive ratio for all axis is 2:1

(stepper:ball

> > > screw) but the BP manual states the ratio should be is 1:1. I
> would
> > > be interested in finding out what ratios others have on their

CNC

> > > BPs and is the BP manuals suggestion of 1:1 is wrong?